Information on the quantity of microorganisms present in a sample and information on the identity of the microorganisms in a sample is often essential in many technical fields, e.g. medicine, agriculture, veterinary science, environmental science and geological exploration, to enable informed decisions to be made.
Techniques for obtaining this information based on the culture of microorganisms are time consuming and often limited in terms of accuracy and practicality due to the potentially unknown and very varied conditions required to effect in vitro growth of the microorganisms in a particular sample.
A more promising approach uses the powerful techniques developed to amplify nucleic acids to characterise the microorganism content of samples, e.g. the polymerase chain reaction (PCR), the ligase amplification reaction (LAR), also known as ligase chain reaction (LCR), and strand displacement amplification (SDA). These methods are sensitive as the techniques used can produce results with only a few copies of the target nucleic acid. They are relatively inexpensive as sample size can be kept to a minimum and the necessary reagents and equipment are now relatively standard, small in size, readily available and cheap. Moreover, the degree of skill required to run these methods is also relatively low. In methods which seek to measure the total amount of microorganisms in a sample, or those that involve a step to amplify the microorganism derived nucleic acid before detection (quantitative or otherwise), a major concern is that the amplification techniques do not universally amplify nucleic acid from the microorganisms in a sample. Any bias against a microorganism will negatively impact any quantification of the total microorganism load of the sample and can provide a false negative in tests to identify, or classify, the type of microorganisms present in the sample.
The present disclosure addresses these problems by providing a primer pair that can permit the amplification of a region of nucleic acid from all, or at least substantially all, prokaryotic cells.